The present invention relates to the general field of fabricating a turbine engine guide vane out of composite material. A preferred field of application for the invention is that of outlet guide vanes (OGVs) of a low pressure compressor of an aviation turbine engine.
In conventional manner, a turbine engine guide vane made out of composite material is fabricated from a fiber preform (obtained by three-dimensional weaving or by draping a two-dimensional fabric), which preform is placed in a compacting and injection mold having an internal recess of shape and dimensions that correspond to the shape and dimensions of the finished molded part. Once the mold has been closed in leaktight manner, a thermosetting resin is injected throughout the recess in order to impregnate the preform, and the assembly is heated in order to polymerize the resin. After this polymerization step, the mold is opened and the finished molded part that is extracted therefrom forms a guide vane having the required shapes and dimensions for use.
The provision of a compacting and injection mold for that type of fabrication needs to comply with a certain number of constraints. Firstly, once the mold is closed it must be completely leaktight for the resin that is injected. Secondly, the fiber preform placed inside the mold must be compacted sufficiently and appropriately to ensure the final fiber content in the resulting part. It is known that during the making of a fiber preform, weaving leads to fibers expanding and creates extra thicknesses in the preform that need to be absorbed.
Proposals have been made for compacting and injection molds that satisfy such constraints. For example, a mold is known that is made up of a plurality of portions that are assembled and held together by bolts, each mold portion, after bolting, exerting a force on one of the surfaces of the fiber preform. Nevertheless, a turbine engine guide vane presents a shape that is geometrically rather complex, such that making such a mold for that type of part requires a large number of parts that are in practice complex to assemble together while also ensuring good leaktightness.
Another compacting and injection mold is known in which closure is obtained by means of a press exerting a force in a single direction, with force deflection columns connected to moving portions of the mold serving to exert compacting forces in various other directions. Nevertheless, the forces needed for compacting a part such as a turbine engine guide vane lead to the molds that are made being complex and not very reliable.